A US woman who shot and killed her husband and two adult children before taking her own life is thought to have committed the shocking crime as a result of being ostracised from the religion she was raised in.

A federal judge sentenced a former Arkansas judge Wednesday to five years in prison — a stiffer punishment than prosecutors recommended — after he admitted giving young male defendants lighter sentences in return for personal benefits that included sexual favours.

Every time I tell a mate I’m doing a story on cryptocurrency, they invariably ask me the same two questions: should they invest their own hard-earned money, and which cryptocurrency will get them a Lamborghini/yacht/island quickest?

In a 60 Minutes online exclusive, reporter Liz Hayes quizzed Australian Prime Minister Malcolm Turnbull on his relationship with the unpredictable Twitter aficionado and US president Donald Trump ahead of their meeting at the White House Friday.

Man charged over Cairns pensioner murder

A 44-year-old Queensland man has been charged over the murder of disability pensioner Robert Duffy.

Police arrested the Cairns man at a Port Douglas address on Thursday and he was charged later in the afternoon.

They refused to confirm he was Mr Duffy's carer, but Detective Inspector Geoff Marsh told reporters he was located in one of two cars belonging to Mr Duffy that police had appealed for help in locating on Wednesday.

A white 2000 Mercedes Benz station wagon was located in Cairns on Wednesday night following a public tip-off, while the 44-year-old man was found driving Mr Duffy's 2004 Holden Commodore.

He will front Cairns Magistrates Court on Friday.

The body of Mr Duffy, 62, was found at his Mooroobool home on Monday shortly after his ex-wife, who hadn't heard from him in three days, raised the alarm.

Det Insp Marsh wouldn't comment on how Mr Duffy had died but said a pathologist had deemed his death to be homicide.